Determining the activation energies and slip systems for dislocation nucleation in body-centered cubic mo and face-centered cubic Ni single crystals

doi:https://doi.org/10.1016/j.scriptamat.2011.03.036

Title: Determining the activation energies and slip systems for dislocation nucleation in body-centered cubic mo and face-centered cubic Ni single crystals

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Abstract

Nanoindentation tests were performed on single crystals of Mo and Ni. The critical shear stress for the first pop-in was {approx}1/7 of the shear modulus in both crystals. The dependence of pop-in probability on load was understood in terms of a thermally activated dislocation nucleation process. Comparison of the activation energies suggests nucleation of full dislocations in Mo and partial dislocations in Ni. The activation energy analysis also offers information on the specific slip system on which dislocations are nucleated.

Authors:

Wang, L. ^[1]; Bei, Hongbin ^[2]; Li, T. ^[1]; Gao, Y. F. ^[3]; George, Easo P ^[2]; Nieh, T. G. ^[1]

University of Tennessee, Knoxville (UTK)
ORNL
University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL)

Publication Date:: 2011-01-01

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:: USDOE Office of Science (SC)

OSTI Identifier:: 1016053

DOE Contract Number:: DE-AC05-00OR22725

Resource Type:: Journal Article

Journal Name:: Scripta Materialia

Additional Journal Information:: Journal Volume: 65; Journal Issue: 3; Journal ID: ISSN 1359-6462

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; ACTIVATION ENERGY; CRYSTAL STRUCTURE; DISLOCATIONS; MONOCRYSTALS; NUCLEATION; PROBABILITY; SHEAR; SLIP

Citation Formats


                    Wang, L., Bei, Hongbin, Li, T., Gao, Y. F., George, Easo P, and Nieh, T. G. Determining the activation energies and slip systems for dislocation nucleation in body-centered cubic mo and face-centered cubic Ni single crystals.  United States: N. p., 2011. 
        Web.  doi:10.1016/j.scriptamat.2011.03.036.

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                    Wang, L., Bei, Hongbin, Li, T., Gao, Y. F., George, Easo P, & Nieh, T. G. Determining the activation energies and slip systems for dislocation nucleation in body-centered cubic mo and face-centered cubic Ni single crystals.  United States.  https://doi.org/10.1016/j.scriptamat.2011.03.036

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                    Wang, L., Bei, Hongbin, Li, T., Gao, Y. F., George, Easo P, and Nieh, T. G. Sat .  
        "Determining the activation energies and slip systems for dislocation nucleation in body-centered cubic mo and face-centered cubic Ni single crystals".  United States.  https://doi.org/10.1016/j.scriptamat.2011.03.036.

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@article{osti_1016053,

  title        = {Determining the activation energies and slip systems for dislocation nucleation in body-centered cubic mo and face-centered cubic Ni single crystals},

  author       = {Wang, L. and Bei, Hongbin and Li, T. and Gao, Y. F. and George, Easo P and Nieh, T. G.},

  abstractNote = {Nanoindentation tests were performed on single crystals of Mo and Ni. The critical shear stress for the first pop-in was {approx}1/7 of the shear modulus in both crystals. The dependence of pop-in probability on load was understood in terms of a thermally activated dislocation nucleation process. Comparison of the activation energies suggests nucleation of full dislocations in Mo and partial dislocations in Ni. The activation energy analysis also offers information on the specific slip system on which dislocations are nucleated.},

  doi          = {10.1016/j.scriptamat.2011.03.036},

  url          = {https://www.osti.gov/biblio/1016053},
  journal      = {Scripta Materialia},

  issn         = {1359-6462},

  number       = 3,

  volume       = 65,

  place        = {United States},

  year         = {2011},

  month        = {1}

}

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https://doi.org/10.1016/j.scriptamat.2011.03.036

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